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Can one’s ability to perform an action, such as hitting a softball, influence one’s perception? According to the action-specific account, perception of spatial layout is influenced by the perceiver’s abilities to perform an intended action. Alternative accounts posit that purported effects are instead due to nonperceptual processes, such as response bias. Despite much confirmatory research on both sides of the debate, researchers who promote a response-bias account have never used the Pong task, which has yielded one of the most robust action-specific effects. Conversely, researchers who promote a perceptual account have rarely used the opposition’s preferred test for response bias, namely, the postexperiment survey. The current experiments rectified this. We found that even for people naive to the experiment’s hypothesis, the ability to block a moving ball affected the ball’s perceived speed. Moreover, when participants were explicitly told the hypothesis and instructed to resist the influence of their ability to block the ball, their ability still affected their perception of the ball’s speed.

Embodied cognition promotes the involvement of the motor system in cognitive processing, such as tool identification. Although neuropsychological studies suggest that the motor system is not necessary for identifying tools, it may still have a functional role in tool recognition. To test this possibility, we used a motor interference task: Participants squeezed a rubber ball in one hand while naming pictures of tools and animals. Participants were faster and more accurate in naming the tools that were oriented with the handle facing away from the squeezing hand than in naming the tools that were oriented with the handle facing toward the squeezing hand. There was no effect of orientation for animals. Given that participants simulate grasping a tool with the hand closest to the handle, this result demonstrates that interfering with the ability to simulate grasping impairs tool naming and suggests that motor simulation has a functional role in tool identification.

Perception of one's body is related not only to the physical appearance of the body, but also to the neural representation of the body. The brain contains many body maps that systematically differ between right- and left-handed people. In general, the cortical representations of the right arm and right hand tend to be of greater area in the left hemisphere than in the right hemisphere for right-handed people, whereas these cortical representations tend to be symmetrical across hemispheres for left-handers. We took advantage of these naturally occurring differences and examined perceived arm length in right- and left-handed people. When looking at each arm and hand individually, right-handed participants perceived their right arms and right hands to be longer than their left arms and left hands, whereas left-handed participants perceived both arms accurately. These experiments reveal a possible relationship between implicit body maps in the brain and conscious perception of the body.